August 20, 2024

Meta-analysis Finds Association Between ADHD Medications and Improvements in Executive Functions

ADHD is associated with deficits in cognitive functions. These include such executive functions as reaction time, motor and interference inhibition, sustained attention, and working memory. 

To what extent can ADHD medications compensate for such deficits? A recent meta-analysis by a European study team has explored this question. It suggests that while medication cannot completely reverse deficits in executive functions, it can lead to significant improvements. 

Based on consistent evidence from many randomized double-blind controlled trials (RCTs) measuring behavioral improvements, first line treatment for ADHD is with stimulant medication while second-line treatment (for stimulant non-responders, or poor tolerability) is with non-stimulant medication (atomoxetine, viloxazine, guanfacine and clonidine). 

This systematic literature search yielded eighteen RCTs, not all of which covered the same executive functions or medicines. 

Meta-analyses yielded the following results: 

Reaction Time 

Eleven RCTs, encompassing 925 participants, found a small-to-medium effect size improvement with methylphenidate. Variation (heterogeneity) among these studies was moderate, and there was no sign of publication bias. 

Four RCTs with a total of 286 participants similarly reported a small-to-medium effect size improvement with atomoxetine. Again, heterogeneity was moderate, with no indication of publication bias. 

Attention 

Sixteen RCTs, with a combined 1,335 participants, found a medium effect size improvement with methylphenidate. Heterogeneity was moderate, and there was some indication of publication bias. No effort was made to correct for publication bias. 

Three RCTs, encompassing 254 persons, found a medium effect size improvement with atomoxetine. Heterogeneity was moderate, with no evidence of publication bias. 

Inhibition 

Thirteen RCTs, with a total of 1,201 participants, found a small-to-medium effect size improvement with methylphenidate. Heterogeneity was moderate, with marginal indication of publication bias. 

Six RCTs with a combined 753 individuals, reported a medium effect size improvement with atomoxetine. Heterogeneity was high, but there was no evidence of publication bias. 

Working Memory 

Nine RCTs, with a total of 1,025 participants, found a small-to-medium effect size improvement with methylphenidate. Heterogeneity was moderate, with no indication of publication bias. 

Three RCTs with a combined 132 individuals, reported a statistically nonsignificant small-to-medium effect size improvement with atomoxetine. Heterogeneity was moderate, with no indication of publication bias. The nonsignificant outcome may have been due to the much smaller number of participants. 

The team concluded, “these meta-analyses of chronic effects of stimulants and non-stimulants on executive functions in ADHD showed significant improvements with both methylphenidate and with atomoxetine in all cognitive domains tested with relatively similar effect sizes, and no statistical differences between them. The findings hence suggest comparable positive effects of both ADHD medication types on the most relevant executive functions in ADHD, suggesting for the first time that stimulant and non-stimulant ADHD medications, when taking [sic] longer-term, not only improve behavioural symptoms of ADHD, but also improve executive function performance, and to a similar degree.” 

Ferdous Isfandnia, Sahid El Masri, Joaquim Radua, and Katya Rubia, “The Effects of Chronic Administration of Stimulant and Non-stimulant Medications on Executive Functions in ADHD: A Systematic Review and Meta-Analysis,” Neuroscience and Biobehavioral Reviews (2024), https://doi.org/10.1016/j.neubiorev.2024.105703

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NEWS TUESDAY: Decision-making and ADHD: A Neuroeconomic Perspective

The Neuroeconomic Perspective 

Neuroeconomics combines neuroscience, psychology, and economics to understand how people make decisions. Neuroeconomic studies suggest that brain regions responsible for evaluating risk and reward, including the prefrontal cortex and dopamine pathways, function differently in individuals with ADHD. These insights are crucial for developing more tailored interventions. For example, understanding how ADHD affects reward processing might inform strategies that help individuals resist impulsive choices or increase motivation for delayed rewards.

Understanding Decision-Making in ADHD 

We know that decision-making is a sophisticated process involving various cognitive procedures. It’s not just about choosing between options but also about how to weigh risks, rewards, and potential future outcomes; Attention, motivation, and cognitive control are core to this process. For individuals with ADHD, however, this neural framework is affected by impairments in attention and impulse control, often resulting in “delay discounting”—the tendency to prefer smaller, immediate rewards over larger, delayed ones.

This propensity for impulsive decisions is more than a personal challenge; it has broader societal and economic implications. Previous studies have shown that these tendencies in ADHD can lead to issues in academics, work, finances, and personal relationships, emphasizing the need for targeted support and interventions.

Implications and Future Directions 

This review highlights a need for continued research to bridge the gaps in understanding how ADHD-specific cognitive deficits influence decision-making. Viewing ADHD through a neuroeconomic lens clarifies how cognitive and neural differences affect decision-making, often leading to impulsive choices with economic and social impacts. This perspective opens doors to more effective interventions, improving decision-making for individuals with ADHD. Future policies informed by this approach could enhance support and reduce associated societal costs.

November 26, 2024

Exploring the Link Between ADHD and Student-Teacher Relationships: A Meta-Analysis

Children with ADHD face significant challenges in academic and social settings, often including difficult interactions with teachers. This meta-analysis investigates the quality of student-teacher relationships for children with ADHD, focusing on two key dimensions: closeness and conflict. By synthesizing data from 27 studies encompassing 17,236 participants, the study aims to provide a comprehensive understanding of these dynamics and inform interventions to support both students and teachers.

Methods

A systematic review was conducted using databases such as PsycInfo, ERIC, and ProQuest. Researchers identified 47 effect sizes from 27 studies, examining the association between ADHD symptoms and the quality of student-teacher relationships. Relationship quality was assessed through two primary dimensions:

  1. Closeness – Warmth, positivity, and openness between the student and teacher.
  2. Conflict – Hostility, negativity, and tension in interactions.

Eight moderator analyses were also performed to explore how factors like grade level, gender, ADHD presentation, and comorbid conditions influenced these relationships.

Summary

The findings reveal that children with ADHD symptoms typically experience relationships with teachers characterized by lower levels of closeness and higher levels of conflict. Notably, externalizing behaviors such as hyperactivity and impulsivity are more strongly associated with conflict than inattentive symptoms. Moderator analyses showed that factors like gender, ADHD presentation, and age influence the severity of these relationship dynamics. For instance, younger children and those with hyperactive-impulsive presentations tend to have higher conflict levels with teachers.

Additionally, the research emphasizes the reciprocal nature of these relationships: ADHD symptoms may exacerbate teacher frustration, while negative teacher-student interactions can intensify student behavioral challenges.

Conclusion

This meta-analysis highlights the critical role of student-teacher relationships in the development of children with ADHD. The findings underline the need for targeted interventions that foster positive teacher-student interactions and reduce conflict. Addressing these relationship dynamics could enhance academic performance, social integration, and emotional well-being for children with ADHD. Future research should explore the causal pathways between ADHD symptoms and relationship quality to better inform educational strategies and support systems.

November 25, 2024

Patterns of Child and Adolescent Psychiatric Admissions During COVID-19: Key Insights from Clinical Data

A recent study from Istanbul sheds light on how psychiatric admissions and diagnoses changed during the first few months of the pandemic compared to previous periods, offering critical insights for parents, clinicians, and policymakers. 

This study, conducted by a team of researchers led by Ozalp Ekinci, examined psychiatric admissions among children and adolescents during 2019 and 2020. 

By looking at diagnosis rates for various psychiatric conditions, the researchers aimed to pinpoint shifts in the mental health landscape as a direct response to the pandemic.

Findings: A Closer Look at Diagnosis Patterns

The analysis revealed several notable trends in psychiatric diagnoses among children and adolescents:

  1. Autism Spectrum Disorder (ASD): ASD diagnoses were notably higher in the early pandemic phase (6.4% in Group A) compared to the same period in the previous year (3.6%). This increase could reflect heightened stress or changes in routines that may have exacerbated underlying symptoms, leading to more frequent clinical presentations.
  2. Obsessive-Compulsive Disorder (OCD) and Tic Disorders: OCD and tic disorder diagnoses also saw a rise, increasing from 1.7% in 2019 to 2.9% during the pandemic’s onset. It’s possible that pandemic-driven anxieties and hygiene concerns, as well as disruptions to typical routines, may have worsened symptoms in those predisposed to OCD and similar disorders.
  3. Intellectual Disability (ID): Diagnoses for ID rose from 2.1% (Group C) to 3.7% (Group A). This increase highlights the challenges faced by children with developmental and intellectual disabilities, who may have experienced heightened difficulty adapting to the many changes imposed by the pandemic.
  4. Attention-Deficit Hyperactivity Disorder (ADHD): ADHD diagnoses were significantly higher in the pandemic phase (59.8% for Group A vs. 49.7% for Group B). With altered school structures, remote learning, and restricted socialization, ADHD symptoms could have been amplified, making it harder for children to concentrate and adhere to routines.
  5. Depression: Depression diagnoses also saw a rise (4.1% in Group A vs. 2.2% in Group C). Isolation, disruption of daily activities, and reduced social interactions likely contributed to increased depressive symptoms, particularly in adolescents who rely heavily on peer support.
  6. Conduct Disorder (CD): Interestingly, CD diagnoses were lower during the pandemic phase compared to pre-pandemic levels (3.6% in Group A vs. 6.4% in Group B). The reduction in face-to-face interactions and less exposure to traditional school settings may have lessened some of the typical triggers associated with conduct-related issues.
Implications

This study’s findings highlight some key takeaways that can guide mental health support efforts for children and adolescents:

  1. Increased Need for Early Support in Neurodevelopmental Disorders: The rise in ASD and ADHD diagnoses points to the need for specialized support in times of crisis, particularly for children who depend on routine and structure. Families and educators should work to create consistent environments that help manage symptoms.
  2. Addressing Pandemic-Induced Anxiety: With heightened cases of OCD and tic disorders, it’s clear that the pandemic’s emphasis on cleanliness and health may have intensified anxiety-driven behaviors. Future mental health responses should include strategies to manage health-related fears and equip children with coping skills.
  3. Supporting Emotional Resilience in Adolescents: Depression was notably higher among young people during the pandemic onset, suggesting a critical need for access to counseling and peer support, especially in times of isolation. Developing robust virtual mental health resources and promoting mental well-being in schools can help support children and adolescents both in and out of school.
  4. Recognizing the Complexity of Behavioral Changes: The drop in conduct disorder diagnoses during the pandemic suggests a link between behavioral disorders and social settings. Understanding these dynamics could lead to more tailored interventions that account for environmental factors impacting behavior.
Conclusion: 

As we continue to see the effects of the COVID-19 pandemic on mental health, studies like this one serve as important reminders of the unique mental health needs of young people. Supporting children and adolescents through proactive and targeted mental health services—especially during times of crisis—will be crucial to fostering resilience and well-being in future generations.

November 19, 2024